1. Field
The disclosed subject matter relates to devices, systems, and processes useful in controlling a trailer connected to a vehicle.
2. Description of the Related Art
People have long been using vehicles including automobiles, sport utility vehicles, and/or light trucks to tow trailers for expanded utility and mobility. FIG. 1 schematically illustrates a tow vehicle 100 and a trailer 101 connected in a manner known in the art that permits the trailer 101 to pivot relative to the tow vehicle 100. The vehicle 100 includes a power train 106 and a steering mechanism 108. The power train 106 propels the vehicle 100 and the trailer 101 via a traction force F0 in a forward direction (or in a reverse direction) in any manner known in the art. FIG. 1 represents the direction of the traction force F0 when the vehicle 100 and trailer travel in a reverse direction. The steering mechanism 108 is configured in any manner known in the art to permit the operator to direct the vehicle 100 to the operator's left or to the operator's right relative to ground.
When traveling in a forward direction, the trailer 101 generally follows the path of the tow vehicle 100. The operator usually is required to compensate for the trailer with use of an increased turning circle. Use of a trailer 101 also typically results in decreased acceleration/deceleration and thus requires increased ramp up distance for a desired terminal speed, and also requires increased stopping distance. Regardless, the operator inputs for pulling the trailer 101 in the forward direction are very similar to those for directing the vehicle 100 without the trailer 101 in tow.
By contrast, when traveling in a reverse direction, the tow vehicle 100 pushes the trailer 101 as indicated by the direction of the traction force F0 in FIG. 1. Operator input is often different when in the reverse direction as compared to when in the forward direction in order for the operator to maintain control. One reason for this is because the pivotal connection between the trailer 101 and the vehicle 100 can complicate the input by the operator of the vehicle 100 when directing the path of the trailer 101. For example, the steering input required to initiate turning of the trailer 101 to the left relative to the operator is in a direction that turns the vehicle 100 to the right. Other variables that can alter the steering input from the vehicle 100 include: different surface inclinations between the vehicle 100 and the trailer 101; a difference in surface type for the vehicle 100 and the trailer 101 (e.g., concrete and sand); uneven surfaces of travel; small obstructions (such as rocks, tree roots, small logs, etc.); and/or other influences that can impart a steering input to the trailer 101. As a result, the vehicle operator may be required to constantly adjust directional input (i.e., left, right, forward and/or reverse) and/or speed input (e.g., fast, slow, stop) in order to steer the trailer 101 in the desired reverse direction. This can increase the time and difficulty for the operator to maneuver the trailer 101 in a reverse direction. An inexperienced vehicle operator can exaggerate this condition because there can be a tendency to overcorrect for undesired trailer direction with incorrect directional input and/or unnecessary speed input.
Thus, it is desirable to provide a control system and method that can permit an operator to steer a vehicle and trailer in a reverse direction with confidence and accuracy, and that can also enhance the efficiency and safety of the maneuver, regardless of the experience level of the operator of the vehicle.